The present invention relates to moving equipment, such as railroads and the like, and in particular to a system for obtaining a preselected number of data samples from the moving equipment while passing through a selected portion of its path of travel independent of the speed of travel.
Railroads are commonly provided with various types of scanning devices along their track sites which extract information from passing railroad cars. One such scanning device may, for example, be a hot bearing detector such as that disclosed in U.S. Pat. No. 3,545,005 and marketed by the Servo Corporation of America of Hicksville, New York under the trade name HOT BOX DETECTIVE. As each wheel of the train enters a scanning zone, an infrared scanner generates a waveform indicative of the temperature of the bearing for that wheel. Information can be obtained from the waveform as to whether the bearing is operating properly or not. Such scanning systems have heretofore been real time analog systems. However, with the increasing use of microprocessors, it is desirable to obtain such information in a discrete form for subsequent processing. To this end, it is necessary to obtain discrete information from the scanner as the wheel passes through the scanning zone. The problem in obtaining such discrete information is that the equipment has no way of knowning at what speed the train will pass through the scanning zone and hence the rate at which data is extracted from the scanner must be totally independent of train speed.
In view of the above, it is a principal object of the present invention to provide a system for obtaining a preselected number of samples from a scanner viewing an object moving through a scanning zone independent of the speed at which the object moves through the zone.
A further object is to provide such a system which utilizes available components and would be readily compatible with existing equipment.
A still further object is to provide such a system which, in addition to being independent of the speed of the moving object is also independent of the direction of the moving object.
Still further objects and advantages will become apparent from the following description of the present invention.